The invention relates to improvements in methods of grinding arcuate surfaces, and more particularly to improvements in methods of grinding arcuate surfaces in form grinders or surface grinding machines of the type wherein the workpiece and the material removing tool can perform angular and translatory movements. Still more particularly, the invention relates to improvements in methods which involve translatory movements of the workpiece and of the grinding tool in directions which are selected as a function of the curvature of the surface to be treated.
In accordance with heretofore known methods, an arcuate surface of a workpiece is treated by a grinding wheel while the workpiece rotates or orbits about an axis which includes the center of curvature of the surface that requires treatment. This is considered desirable and advantageous because the workpiece must only perform pure angular movements but no translatory movements with reference to the grinding tool. A drawback of such method is that, if the radius of curvature of the surface to be treated is large or very large, the workpiece must be mounted on a large or very large rotary support, e.g., on a turntable whose axis intersects the center of curvature of the arcuate surface. Alternatively, it is necessary to provide a complex system of levers and/or links to move the workpiece during removal of material from its arcuate surface.
In accordance with another prior proposal, arcuate surfaces of workpieces are treated in a grinding machine by causing the workpiece to perform a first translatory movement and by causing the grinding wheel to rotate and perform a different second translatory movement. For example, the workpiece can be moved in parallelism with the supporting surface of its table and tangentially of the rotating grinding tool, and the grinding tool is then caused to move at right angles to the direction of translatory movement of the workpiece. This results in the treatment of an arcuate surface on the workpiece. Such prior proposal exhibits the drawback that the point where the grinding wheel applies a grinding force to the workpiece and the direction of action of the force do not remain constant.